Philips a 22 ah 578 pwr service manual

Page 1

A 22AH578/00/16

Servioe
Servgoe
SerVIce

Part 1

15862A

Circuit Description

TECHNICAL DATA
Continuous power : 210 Watts/Channel Signal to noise ratio 2 100 dB
Band I 20-20,000 Hz Input sensitivity : 1 Volt
Total harmonic distortion : 0.08 % Rated impedance : 50K 9
Load 1 8 Q Sub-Sonic filter, at 10 Hz : 12 dB/Octave
IM distortion, at rated power : 0.08 % Inputs : 2
Distortion, at 2 watts Speaker terminals : 2 sets
THD : 0.02 % .
IM (SMPTE 4: 10.02 % Power supply . 120/220 V 50/60 Hz

. Power consumption, at 10 %
Continuous power

at 1,000 Hz, .08 % THD : 250 Watts/Channel mad 9" i 730 Watts
Frequency response, t 0.5 dB : 10.30900 Hz Dimensions : 200x457x381 mm
Separation, at 1,000 Hz : 60 dB Weight 3 285 kg
Damping factor

at 8 9 load : 90

DESCHDHOH des crculls Schaltungsbesohrelbung Kredslobsbesknvelse Kretsbesknvelse Krersbesknvmng Toimmlaseloslus Descnzione del circurio Descrlpiion del circuiro

Stores! to modification

4822 725 12784

Printed inThe Netherlands

Page 2

11

__ PART OF FRONT BB |
-1; 5V ASSY 703871 |
l 3 me. .322 '
\ozla ___ r 107. 47K 7212.:
1 m l_.H
iooc ominl_r\if)§n mm 2min \\ if? at? l_1\vl m5
' lCIOSA \\l or? o/ moan \ 04v lClOIA
l W sizllal/ , 3 642113 /1/ 155g £M sy'l
. / H150 6121 R154
4 g, L/ Q
3' / m m °"
355m 1 6 ~ W
as one .w
my
1 234m , .2

JQ PART 6F_ PROTECTION ,1,
l-lfk an, ASS'Y 703673 ,2 1
. we.
| 1 7 my 7 7 7 m ,3;
a... l T v
, , ,2 d \ :ri .
[Q 0213© 0215 [0217 Eff \ i .0302 m N .1 $01.3 _ 44w
~ 2 1 _ 1 *asos £374 4 x __
i-6-¢7# 1 l 0302 Q 1 lBlJK ._ 5_
, 232N2 o 02 "1 0504
7' i Wspmo/ i j l
3x 1 153191 13)? ex _ 1 l m 1 ~av I
7 355m (1314 ' ,, , 1 Dino: I
2°332%52 l m 232 2 8v s i new
m was ,
Q 1
232m izfifiz l
wont: Magi;
may
1210
555m
7 ___444511
232N2vzw g_-
. mm
0212 e214 0215 W W l Hg,
Q Q l m eapl .33: m 1 a w
i . W «mm , him
321 lav-4 R309 APEX-f mm
M a
, l Rel .1; W 1 Ling)? Q mm mm MUTE OFD
T T g 3" " 0313 ASSY_ 7083671
355m 0303 232,42 0315
la?! 232: 4 * 0307 232N2 ,5
7, 7 0305 1 . 232N2 . s
>* 5. W 232N2 . , o, 15 3.-.
«J: . i ~47 .,n--- ,, 7341--- 1
1 ,_ A- i .
Risa -_ 5V _-
m
m
rrfi '29:

10213 0215,» 0217 i
To a

fl

2d through
it receives
goffers DC
{ source is
énd R152.
be applied
at (pin 2).
tier (pin 1,
tions. This
conditions.

_ifima

I R15
om 01-2

2m 5
am In? '3???)

lBMEG

, Li; mas-1;"?
4700 m
3 l if" on)
355' m" 234p. PART OF FRON

tea

was

7,3100 ~ :

"5V ASS'Y 70387l

The gain of IC106 is controlled by the feedback from a
network consisting of R151, R152 and R149, which is
applied to the inverting input (pin 2).

The output of lC106 (pin 1) is half-wave rectified by
D111 and applied to the sample and hold" circuit com-
prised of C121, R154 and D111. The sample and hold
circuit is used to increase the duration of the DC level
applied to the input of |C107 (pin 3). This action damps
the level meter indication for more accurate readings. The
design of the circuit allows C121 to charge quickly and
discharge slowly. C121 constantly charges and discharges

11%

isuum

with reference to the aUdio signal.

The voltage developed by 0121 is applied to the input of
|C107 (pin 3). lC107 functions as a voltage follower and
offers a high input impedance for minimum loading of the
input signal, while its low output impedance is required
to drive the level meter, The signal at the output of 10107
(pin 1) is coupled directly to the inverting input (pin 2).
This feedback insures 10107 operates with a gain of unity.
Simultaneously, the output of |C107 (pin 1) is applied
through R155 to the positive terminal of the level meter,
which indicates the instantaneous peak power applied to
the speaker.
CS 62 292